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Published a couple blog posts on TPMS Accuracy. First one compares the pressure accuracy of 12 sensors on a single pressure chamber. The second one looks at the Temperature reports in cool ambient after I left Perry. I will be posting next week on the result when it is cold. We will have to wait until July for warm to Hot temperatures

Based on questions I received after my tire seminars in Indy and some statements overheard at various TPMS vendor booths and in other seminars, I decided to offer a detailed example of how I set my TPMS for those that might be wondering how to get the best possible "early warning" from their system. HERE is the link to my blog with all the details for those interested.

I thought posting this example might help those with the recurring question of "How much air should I use?" +++++++ I received this question. "I am a newbie. Just 5 weeks with my 2017 Bay Star 3113. I need some help understanding just what would be the correct or appropriate tire pressure on my coach. When loaded with my wife, dog and self, partial food and clothing, tools, chairs, BBQ ladders, 2/3 water, full gas and propane and misc stuff I got the following from the CAT scales: Front axle - 7,300. Rear axle - 13,260. Here is my dilemma: The dealer delivered the coach with about 85 lbs. per wheel cold, but when I use the Michelin Tire pressure chart for my 235/80R 22.5 XRE tires should be just 75 lbs! I am concerned that they will be "underinflated" and could build up excess heat. Should I keep the 85 lbs or lower the pressures?" ============== My reply: Welcome to RV fun. For all things tires (except buying) I obviously suggest you check my blog. I don't expect folks to remember everything but if you spend a few minutes checking it out, you can learn how to use the "Label List" on the left to find a post of the topic of interest. There is also a search box in upper left. Now to your specific question. 1. We want to know the heaviest load on your tires and since few RVs are perfectly balanced side to side for weight we ideally want to know the "4 corner weight" to learn the heavier end for each axle. lacking knowing that number IMO we can do a rough calculation by using 53% of the axle scale weight for the RV when it was fully loaded (the expected heaviest it will ever be). 2. 53% of your front would be 3,870# and rear would be 7,030# or 3,515 on each dual. 3. Looking at the Michelin load tables we find for your size at 85 psi can support 3,975 for single (front position) and 80 psi supports 7,050# for two tires in dual position. Yes we always round up. 4. Based on the above your MINIMUM inflation would be 85/80 This is the number I would use for the low pressure warning numbers on your TPMS. 5. I recommend adding 10% and again rounding up that means 93/88 psi for your Cold Inflation Pressure or CIP In your case given the close numbers for the front load I would be comfortable using 90 psi all around as a single number is easier to remember. This 10% gives you a nice cushion so you do not have to chase your tire pressure around whenever the temperature rises or falls. You could even get down to 85psi before needing to "top off" the tire pressure again. 6 All tires on an axle should be inflated to the same level for improved handling and response in an emergency situation. 7. I would set the TPMS High Pressure warning to 110 to 115 psi and your high temperature warning level to 160F. 8 Remember CIP means when tires are at ambient temperature and have not been in direct sunlight or driven on for at least two hours. Finally, In your case you are close to some numbers when we round so if your RV is more balanced than my suggested 47/53% you may be able to lower my suggested inflations by 5 psi but only when you confirm your heavier end is less than 53% of the total. +++++++++++++++++++++++++++++++ PS The above post will be on my blog in a few weeks. You folks just got the "Advanced notice".

As I mentioned in another post, I received a TireMinder TPMS system from wife and kids for Christmas. The owner's manual left me with a fundamental question and no answer --> "How to store the transmitters / monitor when not in use?" My toad (a 2016 Jeep Wrangler Unlimited) is my everyday commute to/from work vehicle in Houston. As such I most definitely would not leave the transmitters screwed to the end of the Jeep valve stems. While I trust my "neighbors" at the RV storage facility, I don't know if I trust them enough to leave $45 each transmitters attached to the motorhome tire valve stems. Additionally, the owner's manual states battery life for the transmitters is ~one month. My wife and I use the motorhome mostly for long weekend outings every 4-8 weeks when it's not LSU football season when we use it every one to two weeks. My thoughts about "storage and reactivation" between motorhome uses are: Remove each transmitter, then remove the battery and place both is a small ziplock bag that is labeled for each tire position use the supplied alligator clips to disconnect the signal booster from its 12 volt supply Before a new outing, install the transmitters on their original tire positions. The TireMinder monitor is supposed to "remember" the transmitters even when the monitor is turned off. Is the above a reasonable approach? Your thoughts and guidance please!

My family gave me a TireMinder TM-77 TPMS system for my motorhome and Jeep for Christmas. Due to career demands/business travel, yesterday (Sunday, 1/20/17) was the first opportunity I had to open the TM-77 box. Included in the box is Minder Research's newest signal booster called the Rhino Booster --> http://www.minderresearch.com/tireminder/tireminder-rhino-booster/ The instruction manual says "for best performance" install the signal booster under the motorhome using the zip ties included in the box. This installation seems "flimsy" at best as zip ties over time can break. The instruction manual also says the signal booster can be installed in a storage compartment near the rear of a motorhome. The passenger side rear compartment of my 2007 Damon Astoria motorhome contains the Progressive Dynamics brand power converter and just some lightweight items (jumper cables, wheel cover wrench, traffic warning flag kit, etc.) as that compartment is not designed for much stuff (only has a heavy duty plastic floor). That compartment seems ideal for the Rhino Signal Booster as I could secure it to the wall of the compartment and tap into the compartment light wires to power the signal booster. What is the forum's experience installing a TPMS signal booster installed on a rear compartment of a motorhome? Will the power converter affect the performance of the signal booster? I greatly appreciate the wisdom and experiences of the FMCA forums!!

Over the past few months there have been a couple items in the news and on the Internet about tire failures on RVs and buses. The videos are pretty dramatic. http://tinyurl.com/h4f7ykr http://tinyurl.com/gmvclne Most on this forum are in motorhomes. Many also pull a toad but a few own or have friends with trailers or may even find themselves pulling a trailer ( See our Presidents Message in November FMCA magazine) so I will also include some information for those times. First, for tire failure on toad or trailer or the rear duals or tag of a motorhome it is critical that the driver is notified as soon as possible that there has been a failure or that one is about to occur. The only way I know of gaining this knowledge is with a TPMS that can alert the driver of air loss. Some TPMS can even alert the driver in the first few seconds when the inflation has dropped just a few psi from the hot running pressure. If you do not run a TPMS then you will not learn of the pressure loss before damage has been done, as you will be depending on passing motorists to get the driver's attention. By this time, damage has been done but hopefully the toad or trailer hasn't rolled over or separated from the motorhome which could raise the level of severity of consequences dramatically. For motorhome or bus drivers the failure of a front tire can mean a significantly different outcome, as there is the real potential of a complete loss of control if the wrong response is taken. Here we know that a warning of initial air loss may provide enough time for a thoughtful response from the driver but even having a TPMS is not a 100% guarantee as there are failures that do not involve air loss. So the question then is what actions need to be taken in the first fraction of a second after a front tire comes apart? Thankfully there is a good instructional video of what a driver needs to do. Here is one from Michelin http://tinyurl.com/hjuyu4m and another similar video. Yes, the advice is not intuitive to the average driver but it can work. It has been demonstrated numerous times that there is both proper and improper driver response to a tire failure. Sadly many drivers have ended up turning an inconvenience into a tragedy. A driver needs to stop and think about what to do and to take a moment - frequently - to help implant the correct response so it can become an automatic response. You do have plenty of time to think about this as you drive down the highway. I would suggest that if you spent as little as 10 seconds thinking about the correct response of maintaining control first then slowing down second rather than just stomping on the brakes just once an hour every hour when driving you might find that the action might become automatic. We all know that practice and repetition can make athletes better at their "game" well in this case practice, at least in thought, can make you a safer driver in the "job" of getting yourself and family safely to your destination a reality.

I have read a number of forum posts here and on other RV forums on people's concern about the different readings from their TPMS. I have finished testing my test fixture and will be offering a FREE service (although a donation of a can of Coke would be accepted ) of testing your TPMS to see what the variation is between your sensors and my calibrated pressure gauge. We will also be able to test each sensor for response time when it senses an air loss. Time & location will be announced at both of my tire Seminars, currently scheduled Wed 3:15 PM and Fri 11 Am

OK this is a long post and may put some folks to sleep, but if you can wade through it I would appreciate feedback. Comments appreciated or direct email might be best for some folks. Tireman9 at gmail.com I am trying to develop a comprehensive statement oh how to set both Cold Inflation Pressure and TPMS warning levels. I also need to keep this simple enough so anyone can follow the instructions. So what do you think? I feel the CIP should it be the minimum inflation based on actual measured load of that individual RV plus a margin, even if the RV industry doesn't want this because they would have to provide larger or higher rated tires to future models. Owners can read their inflation and calculate the CIP. Suggesting a margin on load involves the tables and additional interpretation. +++++++++++++++++++++++++++ Steps for setting CIP and TPMS pressure warning levels: 1. Weigh the coach and learn 4 corner weights or at least get axle weights and assume a 47/53 side to side load split on each axle to accommodate some of the identified unbalance in RVs. 2. Using the heavier end load for each axle or the 53% figure, use Load Inflation table to learn the minimum inflation needed to support that load. 3. Establish the CIP to be the minimum inflation in step 2 + 10% + round up to next higher 5 or 10 inflation level to get an easy to remember inflation for the CIP. Example Load table gives 80 psi + 10% = 88psi and round up gives 90 psi. Example Load table gives 110 psi +10% = 121 and round up to 125 4. Set the low pressure warning level of a TPMS to the inflation level in step 2 above to ensure the tires are never operated in an overloaded condition. 5. Set the high pressure warning level to 120% of CIP ++++++++++++++++ Reasoning for #1. IMO a 45/55 would cover more RVs but might be too much unbalance and not reflect the majority (lets say 90%) of motorhomes so I am suggesting the 53% as a compromise. I can only guess at the statistics needed to cover 80 or 90% of the market. Reasoning for #4 Some TPMS sellers say to set the low warning level to -10% and other say -15% or possibly lower, of the "baseline inflation" but they do not seem to be clear or consistent seller to seller on what they mean by "baseline". Some will say placard inflation others say the inflation in the tables. I believe the -15% inflation level for warning level for TPM was taken from the passenger car warning level but that ignores the fact that passenger car inflation levels are not set to the pressure needed to support the load but at a higher level some significantly higher as handling or fuel economy are a driving force for light ( under 10,000#) vehicles. Reasoning for #5 With pressure increasing by about 2% per 10°F a 20% rise in pressure would translate to a temperature rise of 100°F which would be significant and may indicate some problem or excess speed for the conditions.. Note the default TPMS High temperature warning of 158°F is not reflecting the actual tire temperature as there is cooler of the sensor and the hottest part of the tire is hotter than the contained air average temperature. ==================== Are the suggested guidelines clear enough? Do you think my reasoning is logical?

Well, after reading and reading and reading, and researching, finally, decided to go with the TST TPMS, which I ordered today. Won't get it to install until we arrive in NY next week. Then a 1k mile trip to test them out. I sure hope they work without any headaches. One thing, it appears that the customer service with TST is outstanding. Customer service is the most important consideration for me, along with product quality. If they can be equalized, then it's a no brainer. Along with Value, hopefully it is a win, win. There were less expensive and more expensive tpms units out there, but tst kept coming to to the surface. Since 0'76, we have had a blow out on one TT, and 2 blowouts on a former class c. Luckily, no vehicle damage occurred on either. We were approaching a Semi on I65, and before we caught up to him, a trailer tire blew. Not much traffic, and we ended up dodging flying tread, etc until we could get out of the way. Tires get a lot of my attention, now I will have another MH toy and a sister for the GPS to play around with.

Hello. We just bought a 2000 Newmar Dutch Star with 29,000 miles and will be taking our first trip in April to Disney. The previous owner talked several times about tire blowouts and the importance of tire maintenance. I am about to get a tire monitoring system for Christmas, I was all set to buy the TST 507 system with the user-friendly battery replacment. I then came across the Tire Safeguard system in this month's article with the ability to add air without removing the sensor. Does anyone have pros or cons on either system? I never realized there was so much about load weight, corner load, axle load. I am just about in overload myself just trying to figure out what I should use for tire pressure ... lol Thank you, Frank from Mass

I am disappointed that the Tire Monitoring Systems article in this month's issue of Family Motor Coaching left out what I feel is one of the best systems on the market. Truck System Technology's TST 507 beats most of the systems listed in the article -- hands down, in my opinion. It shows pressure and temperature. And, it has user-replaceable batteries. Their customer service is one of the best I have found, and I feel the company is as honest and as customer-oriented ever. I heartily recommend them to anyone. rvjer